JPH0836410A - Method and device for preventing interfernece between robots - Google Patents

Abstract

PURPOSE:To prevent the interference between robots without setting an interlock signal with a simple device constitution at the time of operating plural robots by sharing one memory among plural robots and reciprocally setting flags in the memory space to express the operation areas of these robots. CONSTITUTION:This device consists of a shared memory 2 which artificially reproduces the space where plural robots operate and an interference check part 3 which receives operation signals from robot controllers 10 and 20 to write the flags in the shared memory 2 and iddues a wait command to controllers 10 and 20 of a robot at the time of receiving the flag write request from this robot to the area where the flag is set in the shared memory 2. Flags are set in operation routes of robots in the memory space, and the operation is started after positions in the operation space are reserved in the memory 2. Only one robot can set the flag in the same area of the memory 2 at a time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interference prevention method and apparatus for preventing interference between robots when a plurality of robots operate.

[0002]

2. Description of the Related Art In recent years, many scenes where robots are used as factory production equipment have been seen. One of the ways in which this robot is used is to install a plurality of robots in one process (stage) and perform work at one time.

In such a case, in order to prevent the robots from interfering with each other by arranging a plurality of robots in a certain space, when one robot enters an area where it interferes with another robot, By sending an interlock signal so as not to enter the area, another robot is prevented from entering the area to prevent interference.

As a method for preventing the interference between the robots, an interlock signal is previously set when the robots come to a position where they interfere with each other so that the robots do not interfere with each other during the operation teaching of the robots. A method to prevent this from being sent to the robot is taken, but to decide the timing of issuing this interlock signal, do you actually operate the robot and set it while the operator confirms the movement of each robot? Or, it is necessary to predict the interference position of each robot by the robot motion simulation and set it by confirming it by a human being, and it takes a lot of time and labor to teach the robot motion, and It is extremely difficult to reliably predict the position and time, the output of the interlock signal is fast,
There is a problem that other robots are stopped for an extra time, or on the contrary, the robots come into contact with each other due to slowness.

Therefore, as a conventional method for preventing the interference of the robot without programming the setting of the interlock signal as described above, Japanese Patent Laid-Open No. 58-22690 discloses the motion of one robot. , The first memory and the position of the obstacle are stored in a second memory having the same memory space.
It is disclosed that the robots are prevented from interfering with each other by comparing the memories. According to this publication, as the obstacles stored in the second memory, the movement loci of other robots that may interfere with each other are set, and the robots stored in the first memory and the second robot are stored. It is possible to prevent interference with the robot stored in the memory.

[0006]

However, in the method described in the above publication, one memory indicating the space in which the robot is operating is provided for each robot, that is, robots that may interfere with each other are stored in the same space. So, in case of 2 units, 2 memories, in case of 3 or more robots 3
It is necessary to prepare three or more memories, and since the stored contents of the plurality of memories are compared, there is a problem that the device configuration and the processing for comparison become complicated. In particular, if only two robots are used, the two memories can be compared with each other, but if three or more robots are used,
Since more than one memory will be compared with each other, it will not be a little time for this comparison process as the number of robots increases as the number of robots increases with complexity, only by comparing which memory and which memory. If necessary, the robot operation may be delayed. There is also a problem of cost increase due to an increase in the number of memories.

Therefore, an object of the present invention is to provide a robot interference prevention method and device capable of reliably preventing robot interference with a simple device configuration when a plurality of robots are operated. Is.

[0008]

According to the present invention for solving the above-mentioned object, a space in which a plurality of robots operate is simulated in a memory, and when each robot of the plurality of robots operates, The operation is started after writing a flag in the area in which the robots operate in the space in the memory so that only one robot can write the flag in the same area in the space in the memory at one time. This is a method for preventing the interference of the robot.

The present invention for solving the above-mentioned object also provides
A space in which a plurality of robots operates is simulated in a memory, the existence of the robots is flagged in the space in the memory, and the memory is used when one of the plurality of robots operates. To see if there is a flag for the space in the memory of the area where the one robot will move from now on.If the flag is not set, set the flag in the area where the one robot moves in the memory. A method for preventing interference of a robot is characterized in that the robot starts standing up, and when the flag is set, the start of the operation of the one robot is put on standby.

Further, according to the present invention for solving the above-mentioned object, one storage means for artificially reproducing a space in which a plurality of robots operate and a state of a flag in the memory are confirmed, and a flag in the memory is confirmed. Interference prevention means for issuing a standby command to a robot when any one of the plurality of robots tries to write a flag in the area where is written. It is a device.

Furthermore, the present invention for solving the above-mentioned object is directed to a case in which one of the plurality of robots performs an operation, and one storage means for simulating the space in which the plurality of robots operate. Interference check means for checking the state of the flag in the memory and for issuing an operation command to the robot when there is no flag in the operation area of the robot. It is a prevention device.

[0012]

According to the interference prevention method of the present invention having the above-described structure, the area in which the robot operates is simulated in the memory so that the robot can be stored in the space in the memory (hereinafter referred to as the memory space). When a robot moves, a flag is set in its movement path to ensure the position in the space where the robot will move in the memory before starting the movement, so that only one robot is stored in the memory at a time. By making it impossible to set this flag in the same area of, the robot which cannot set the flag in this memory space cannot start the operation. Since one of the multiple robots tried to set a flag to start the operation in the same area where the flag was set in the memory space by another robot, the flag cannot be written. Can not do. This prevents interference between these robots.

Further, in the interference prevention method of the present invention, an area in which the robot operates is simulated in memory to set a flag in this memory space to indicate the robot's existing position and movement path. If the robot is going to operate, access this memory space to check the existence of the flag, and then start the robot operation only when there is no flag. By making the robot stand by, interference between robots is prevented.

The interference prevention device of the present invention has a storage means for reproducing the space in which the robot operates, so that the operation and existence position of the robot can be confirmed by writing a flag in the storage means. Detects the writing of the flag of the robot attempting to operate in the area where the flag is written in this storage means, and attempts to write the flag in the area where the flag is set, that is, the movement path of another robot. By outputting a standby command to the robots that try to move inside, interference between the robots is prevented.

Further, the interference prevention device of the present invention has the storage means for reproducing the space in which the robot operates, so that the operation and the existing position of the robot can be confirmed by writing a flag in the storage means to prevent interference. The check means detects that the flag is not set in the storage means corresponding to the operation area of the robot to be operated, that is, confirms that no other robot is present in the operation path, and then operates. By outputting an operation command to the robots, the interference between the robots is prevented.

[0016]

An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a block diagram for explaining a robot interference prevention device to which the present invention is applied. The interference prevention device 1 receives a motion signal from a shared memory 2 which is a storage device for artificially reproducing a space in which a plurality of robots operate, as will be described later, and receives a motion signal from the robot control device, and stores the shared memory 2. When a flag is written and a flag write request is received from the robot in a flag area in the shared memory 2,
The interference check unit 3 is an interference check unit that issues a standby command. The illustrated robot control devices 10 and 20 will be described later.

This shared memory 2 is, as shown in FIG.
Addresses are arranged so that the space in which the robot operates is reproduced as a three-dimensional cube in a pseudo manner. In the present embodiment, the actual operation space of the robot is divided horizontally, vertically, and into 256 depths. It is reproduced as a memory space. The memory capacity required for this is 256 x 3 and 16M
It becomes a byte. The address arrangement at this time is 6 digits in total because addresses in each direction are from 00 to FF (256 addresses), the horizontal direction is the last 2 digits, and the vertical direction is 3 or 4. The first digit and the second digit represent the digit and the depth direction. There is always one memory space reproduced by this shared memory 2 regardless of the number of robots (it does not mean that there is one memory device,
In the present embodiment, there is one memory space of 16 Mbytes, and as a memory device therefor, for example, 16 1M memories and 4 4M memories are required).

When the robot operates, a flag indicating an area in which the robot operates is set in the shared memory 2 before the operation. In the interference check unit 3, therefore,
The data calculated by the motion locus calculation unit of each robot control device is received, first, the address in the memory space corresponding to the received motion locus is calculated, the shared memory 2 is searched, and the calculated address is calculated. When the flag is not set at the same address as, the flag is written at the address which becomes the operation locus. Further, when the flag has already been set at the address in the shared memory 2, the interference check unit 3 transmits a motion standby command to the robot control device that has transmitted the motion locus. In addition, the flag in the shared memory 2 is represented by setting 1 in this embodiment, and the state without the flag is 0. The flag is cleared to 0 when the robot operation is completed.

This will be described in more detail. For example, when there are two robots, robot A and robot B, which may work in the same space and interfere with each other, as shown in FIG. And B controllers 10 and 2
0 is connected to the robot interference prevention device 1, and first, when the robot A starts its operation, the interference check section 3 receives its operation trajectory. Then, an address corresponding to the operation locus in the memory space is calculated from the received operation locus, the shared memory 2 is accessed, and it is confirmed whether the corresponding address is 0 or 1. When no other robot is in the memory space, the data of each address of the shared memory 2 is all 0. Therefore, the interference check unit 3 writes the calculated address and changes the data to 1. In this state, when the interference check unit 3 receives the movement locus for starting the movement of the robot B, the address corresponding to the movement locus in the memory space is calculated from the received movement locus as described above. , The shared memory 2 is accessed to confirm whether the corresponding address is 0 or 1. At this time, since the data of the address is 1 in the area that is the movement locus of the robot A, even if the same address as the address calculated as the movement locus of the robot B is 1
If it is, the writing of data to the shared memory 2 is stopped and the robot B of the robot B control device 20 is stopped.
A standby command is output to the operation command unit 21 so that the robot B does not operate. As a result, the operation of the robot B in the same area where interference may occur is stopped, and the interference between the robot A and the robot B is prevented.

The operation of the robot controller will be described below. The robot controller, as shown in FIG.
It comprises robot operation command units 11 and 21 for issuing an operation command of the robot, and robot trajectory calculation units 12 and 22 for calculating an operation trajectory of the robot based on the command of the robot operation instruction unit. This robot controller is a controller for a general teaching playback type robot, and the robot operation command units 11 and 21 move the robot from one operation point to the next operation in accordance with the operation point of the robot taught. The robot trajectory calculation units 12 and 2 which output a command to move the robot to a point and receive the command.
2 calculates a motion locus from one motion point to the next motion point, and the arm of the robot main body (not shown) that has designated a motion based on this motion locus moves.

The motion locus calculated by the robot locus calculation unit is output as position data in the robot coordinate system, and the interference check unit 3 in this embodiment uses the position data in this robot coordinate system as an address in the shared memory space. Convert. At this time, the position data in the robot coordinate system is the center position of the robot movable part at the operating point of the robot, and the size of the arm or hand of the robot body is not taken into consideration. Add the size of the robot around the address converted from the position data. For example, when the size of the robot arm in the memory space corresponds to three points at 256 division points,
The size of the robot in the memory space is represented by adding two addresses in the horizontal, vertical and depth directions to the address converted from the position data.

The standby command for waiting the robot is
It is designed to be input from the interlock signal reception port of the robot operation command section, and when attempting to operate in the flagged area in the memory space as described above, the interference check section 3 A signal is input to the interlock signal reception port to make the robot operation stand by.

Next, the robot operation and the operation of the interference prevention device will be described with reference to the flow chart shown in FIG.

First, based on a motion command from the robot motion command unit, the robot trajectory calculation unit calculates position data, which is a motion trajectory of the robot to move in the future (S).
1) In the interference check unit 3 that has received the position data, the position data is converted into an address of the shared memory 2 (S2), the address obtained by the conversion is read from the shared memory 2 (S3), and the read address is read. If it is detected that the flag is set (the data of the address is 1), the robot standby command is output (S8), and if there is no flag, the flag is set at the above address of the shared memory ( 1 is written) (S5), and the robot operation command is directly output from the operation command unit (S6). And
When the robot leaves the area in the memory space, the flag of that address is cleared (data is set to 0) (S
7).

As described above, in the present embodiment, when another robot attempts to operate in the area where the flag of the shared memory is set by the interference check unit, a standby command is issued to the robot to cause interference of the robot. This is done by using this robot standby command for the interlock signal for robot prevention that has been used conventionally, without changing the operation program in the robot controller. It is possible to prevent the interference of. However, the present invention is not limited to such a configuration. For example, the operation command to the robot body output from the robot controller is not directly output to the robot body, and the robot operation command is interfered with. It is also possible to prevent robot interference by issuing an operation command from the interference check unit to the robot body so that the robot can operate when the checking device receives it and confirms that there is no flag. . Of course, even in the case of such a configuration, it is not necessary to change the program for robot operation, and by simply interposing the interference prevention device according to the present invention between the robot control device and the robot body, interference between robots can be prevented. Can be prevented.

Further, according to the present invention, not only the interference between a plurality of robots is prevented but also the interference between the robots and other moving obstacles is flagged in the shared memory as in the above embodiment. By standing upright, it is possible to prevent interference between the moving obstacle and the robot.

[0028]

As described above, according to the first aspect of the present invention.
According to the robot interference prevention methods of (1) and (2), a plurality of robots share a single memory defined so as to correspond to the operation space, and the operation areas of the robots are set in the memory space so that flags are excluded from each other. It is not necessary to consider the point of time when the robots interfere with each other when teaching the robot motion, and the robot interference is prevented without providing a program for interlock signal output. be able to.

According to the robot interference prevention device of the third and fourth aspects of the present invention, a single storage means is shared by a plurality of robots, and the movement paths of the plurality of robots are mutually excluded from the storage means. The interference check means detects the state of this flag and prevents a plurality of robots from operating in the area with the flag. Therefore, even if the number of robots increases Since the number of memory devices and the checking operation thereof do not increase, it is suitable as an interference prevention device when operating a large number of robots in the same space without increasing the equipment cost for preventing interference.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating an interference prevention device that is an embodiment of the present invention.

FIG. 2 is a diagram for explaining a memory space according to the embodiment.

FIG. 3 is a flowchart for explaining the operation of the interference prevention device in the above embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Interference prevention device, 2 ... Shared memory, 3 ... Interference check part, 10, 20 ... Robot control device, 11, 21
... Robot operation command unit, 12, 22 ... Robot trajectory calculation unit.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location G05D 1/02 P

Claims (4)

[Claims] 1. A space in which a plurality of robots operates is simulated in a memory, and when each robot of the plurality of robots operates, a flag is set in an area in the memory in which the robots operate. After starting writing, the operation is started, and only one robot can write the flag in the same area of the space in the memory at one time. 2. A space in which a plurality of robots operates is simulated in a memory, and the presence of the robots is flagged in the space in the memory, and one of the plurality of robots operates. In this case, the memory is accessed and the presence or absence of a flag of the space in the memory of the area where the one robot is about to operate is checked. If the flag is not set, the one robot of the memory is operated. A method for preventing interference of robots, wherein a flag is set in an area to be operated, the one robot starts operation, and when the flag is set, the operation start of the one robot is waited. 3. A storage means for quasi-reproducing a space in which a plurality of robots move, a state of a flag in the memory is confirmed, and the plurality of storage areas are stored in an area where the flag is written in the memory. An interference prevention device for a robot, comprising: an interference check means for issuing a standby command to the robot when any one of the robots tries to write a flag. 4. A storage means for simulating a space in which a plurality of robots operate, and a state of a flag in the memory when one of the plurality of robots operates. An interference check device for a robot, further comprising: an interference check unit that issues an operation command to the robot when there is no flag in the operation area of the robot.